Abstract:
:The signals of water in the different compartments of rat sciatic nerve are resolved in the (2)H double-quantum-filtered NMR spectrum, due to their different quadrupolar splittings and relaxation rates. This resolution allowed the independent measurement of the water diffusion coefficients in the different compartments. The water diffusion in all three compartments, the endoneurium, the epineurium and the axon was found to be anisotropic. Parallel to the nerve fiber the average intraxonal water diffusion coefficient was 1.11 x 10(-5) cm(2)/sec, while in the perpendicular direction the diffusion is heavily restricted. The average perpendicular diffusion coefficient ranged from 0.29 x 10(-5) cm(2)/sec to 0.05 x 10(-5) cm(2)/sec for diffusion times of 7 msec and 50 msec, respectively. Assuming restricted diffusion in nonpermeable cylinders, intra-axonal mean diameters of 6.0, 7.4 and 9.0 microm were obtained for nerves taken from three different rats. Magn Reson Med 42:461-466, 1999.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Seo Y,Shinar H,Morita Y,Navon Gdoi
10.1002/(sici)1522-2594(199909)42:3<461::aid-mrm8>subject
Has Abstractpub_date
1999-09-01 00:00:00pages
461-6issue
3eissn
0740-3194issn
1522-2594pii
10.1002/(SICI)1522-2594(199909)42:3<461::AID-MRM8>journal_volume
42pub_type
杂志文章abstract:PURPOSE:To investigate whether saturation using existing methods developed for 3T imaging is feasible for clinical perfusion imaging at 7T, and to propose a new design of saturation pulse train for first-pass myocardial perfusion imaging at 7T. METHODS:The new design of saturation pulse train consists of four hyperbol...
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